Hydroxocobalamin hydrochloride

The consecutive addition of alkyl halide to activated olefins by photoelectrocatalysis (PEC) of hydroxocobalamin hydrochloride allows the construction of extended carbon chains as shown for the synthesis of pheromone queen substance 9. The mild conditions of the B12/PEC reaction are suited for the addition of primary alkyl halides 10 containing a potential leaving group. This is illustrated in the synthesis of endo- and exo-brevicomin (11) (Scheme 4). 

The synthesis of C-glycosides may be achieved by B 2-catalyzed C-C bond formation. Thus, 3-(2,3,4,6-tetra-0-acetyl-a-D-glucosyl)propionitrile (13) can be prepared from acetobromoglucose (12) by reduction with Zn in DMF in the presence of acrylonitrile and 3 mol% hydroxocobalamin hydrochloride. Similarly, the ribo-furanosyl derivative 15 can be prepared from the corresponding acetobromofur-anose 14 (Scheme 5). 

Co(l) Co(lll) Hydroxocobalamine hydrochloride Bi2a Scheme 91 Generation of carbon-centered free radicals by vitamin Bn-photoelectrocatalysis. 

Hydroquinidine hydrochloride, 668 Hydroquinine, 669 (metabolite), 955 Hydroquinol, 669 Hydroquinone, 669 HydroSaluric, 663 Hydrotest, 1003 Hydroxo 669 Hydroxocobalamin, 669 Hydroxyacetamidoflunitrazepam, 624 Hydroxyacetanilide, 849 Hydroxyacetohexamide, 314... 

Hydroxocobalamin (Cyanokit) has been the chelator of choice in Europe and Australia, and has been approved for use in the United States since 2007. It works by combining with cyanide to form cyanocobalamin (vitamin B12 Hall and Rumack, 1987). Hydroxocobalamin has been shown to reduce mortality in rats, mice, and beagles and has the advantage of producing neither methemoglobinemia nor hypotension, as sodium nitrite does (Hall and Rumack, 1987 Borron et al., 2006). Dicobalt-EDTA (Kelocyanor) and 4-dimethylaminophenol hydrochloride (4-DMAP) are other chelators available in Europe, Israel, and Australia, but not in the United States (Hillman et al., 1974 Weger, 1990). 

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